The present invention generally relates to non-volatile data storage devices for use with computers and other processing apparatuses. More particularly, this invention relates to stacked graphene layers employed as solid state storage media, and using a tunable band gap associated with the graphene layers to indicate a bit value stored in the storage media.
Mass storage devices such as advanced technology attachment (ATA) drives and small computer system interface (SCSI) drives are rapidly adopting non-volatile memory technology, such as flash memory or another emerging solid-state memory technology including phase change memory (PCM), resistive random access memory (RRAM), magnetoresistive random access memory (MRAM), ferromagnetic random access memory (FRAM) or organic memories. Currently the most common solid-state technology uses NAND flash memory components as inexpensive storage memory, often in a form commonly referred to as a solid-state drive (SSD). These memory devices generally comprise an array or grid of cells, each capable of reversibly storing data indicated by a form of charge state within the cell that can be changed by a switching event induced by the application of power (e.g., current, heat, etc.) to the cell. All mentioned technologies, however, are limited by their scalability towards smaller process technologies. The primary limitations are related to the interconnect layers with respect to delivering enough power to induce changes in the targeted cells as, for example, needed in MRAM or PCM, or to the limited scalability of the actual memory cells.
In view of the problems outlined above, it appears desirable to find new materials and structures suitable for manufacturing memory cells capable of reversibly storing data, being scalable towards small process technologies, and having low power requirements for sensing data and/or inducing a switching event from one state to another.